长期定位施肥对黑土碳氮储量的影响

以中国科学院海伦农业生态实验站的18 a长期定位施肥试验为平台,研究了在不施肥（CK）、施化肥（NPK）和化肥配施有机肥（NPKOM）条件下,0～100 cm土体剖面碳、氮的分布特征,并在此基础上分析0～100 cm土体碳氮储量的变化。结果表明,与CK处理相比,施用有机肥的NPKOM处理增加了0～60 cm剖面土壤的碳、氮含量,而施化肥NPK处理,只增加了0～20 cm耕层土壤碳、氮含量。从0～100 cm土体碳、氮储量来看,施肥对0～100 cm土体碳、氮储量影响较小,尽管各处理间的变化趋势为NPKOM〉NPK〉CK,但处理间差异不显著。剖面土壤碳、氮含量存在着线性关系,相关系数R=0.991。与无肥CK处理相比,化肥配施有机肥NPKOM处理和化肥NPK处理的C/N有下降趋势,而与NPK处理相比,NPKOM处理的C/N也有所降低,这些结果表明长期定位施肥条件下的土壤剖面碳、氮的变化是相互影响,相互制约。

Carbon and Nitrogen Reserve under Long-term Fertilization Conditions

The reserve and changes of carbon and nitrogen in 0 ～ 100 cm profile were studied,to compare the CK（no fertilizer）,NPK（chemical fertilizer） and NPKOM（chemical plus organic fertilizer）,under various long-term fertilization conditions at the Ecological Station of Hailun,Chinese Academy Science.Results showed that NPKOM increased the carbon and nitrogen contents of 0 ～ 60 cm profile compared to CK,while NPK only increased that of 0～20 cm profile.Compared to carbon and nitrogen reverse in 0 ～ 100 cm profile,there are in an order of NPKOMNPKCK,but no significant difference.There was a line relationship between carbon and nitrogen content in soil profile（R=0.991）.In contrast to C/N of CK,NPKOM and NPK decreased the C/N in soil.Similarly,NPKOM also decreased the C/N in soil compared to NPK.All these results suggested that there has interaction between carbon and nitrogen change under long-term fertilization conditions.